The present invention relates to induction heat cooking apparatus, and more particularly to a multi-unit induction heat cooking apparatus.
Induction heating is well known in the art as an excellent method for heating foodstuff and is finding extensive use in household applications due to its excellent power saving characteristic in favor of resistance heaters and its safety feature in favor of gas ranges. It is desired that a plurality of induction heating coils be provided for enabling individual heating on a simultaneous basis. This requires a plurality of costly converter units to be mounted in a limited space available. Since the converter uses a semiconductor switching device to convert AC power to high frequency energy, usually in the ultrasonic frequency range, the high frequency energy is also coupled to an input side of the heating system; this causes noise to be generated in electrical appliances coupled to the same power source. One approach to avoid the noise is to provide a noise rejection filter in each input power circuit of the inverter. However, this adds to the total cost of multi-unit induction heat cooking apparatus.